1. Field of the Invention
The present invention relates generally to medical devices and methods. More particularly, the present invention relates to a removal and protocol for removing an implanted transcutaneous catheter, such as a tunneled central venous catheter.
A tunneled central venous catheter is a medical device which is placed with the tip of the catheter in the central venous system and which allows for administration of medication, for drawing blood for laboratory tests, for hemodialysis access, and the like. Such tunneled central venous catheters have an intravenous portion and a sub-dermal portion. The sub-dermal portion of has a catheter cuff or other fixation element that embeds into subcutaneous tissue to provide both an“anchor” to hold the catheter in placer and a “seal” to inhibit the intrusion of bacteriaandr other contaminants. Such catheters are usually placed through the chest wall, tunneled under the skin, and enter the central venous system through the subclavian vein or internal jugular vein. The catheter tip is typically positioned in the superior vena cava or right atrium. Cuffed catheters can be also used for peritoneal dialysis and typically have both a subdermal cuff and a muscular cuff. Such cuffed peritoneal dialysis catheters may be inserted into the peritoneal cavity and used for long-term, ambulatory peritoneal dialysis.
Even though cuffed catheters are usually implanted for relatively long times, they are still temporary and must be removed when no longer needed. The presence of the cuff, however, complicates such removal. Almost instantly after catheter implantation, scar tissue, referred to as a sheath, begins to circumferentially form on the cuff and to a lesser extent on the catheter body. Cuffed catheters can remain implanted for months or even years, and the density and durability of the scar tissue increases over time exacerbating the removal difficulty.
Because of the scar tissue, catheter removal usually requires surgical dissection of the catheter and cuff from surrounding scar tissue followed by traction on the catheter for removal of the catheter and cuff. After removal, external pressure is applied to the catheter tract to stop bleeding. Such surgical removal procedures require skilled use of surgical instruments, such as an Iris scissor, a safety scalpel, and a curved hemostat. In difficult procedures, a counter-incision is needed for cuff access, and an incision may also be required at the exit site to widen the skin penetration. Once dissection is complete, the catheter is again pulled with gentle traction. These procedures are often performed in a clinic setting, an outpatient surgery center, or a hospital operating room depending on the patient's condition and the position of the catheter and cuff. Such removal procedures often require consultation with a surgical specialist, and the removal procedure may require 15 minutes or longer to complete including time to achieve hemostasis.
For these reason, improved devices, systems, methods, and protocols for removing implanted cuffed catheters are needed. In particular, it would be desirable if devices and methods were provided which increased the likelihood of successfully removing an implanted catheter without the need for a cut down or other surgical procedure, which reduced the time necessary for removing the catheter, and which decreased the trauma to the patient. At least some of these objectives will be met by the inventions described below.
2. Description of the Background Art
Previous cuffed catheter extraction catheters typically included a C-shaped shaft that was advanced over the catheter and used to dissect the cuff from surrounding tissue. The shaft was typically had a diameter larger than the cuff to allow the shaft to pass into and dissect the scar tissue surrounding the cuff. The shaft could include a serrated end to cut through peri-cuff scar tissue. An inner bead or blade was often rotated to cut the “fibrin sheath” away from the catheter, this allowing the catheter to be removed by traction on the catheter followed by application of pressure over the catheter tract for hemostasis. When used for inaccessible cuffs located far from the skin exit site, such prior extraction procedures often required additional cut-down when the scar sheath disruption was incomplete or when there was difficulty entering through the skin at the catheter exit site. Relevant patents and publications include: U.S. Pat. No. 7,758,590; US20070118148; US20070244490; US20080195130; and US20100241133 US20120203240.